/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 *
 * Author: Adam Dunkels <adam@sics.se>
 *
 */

#include "lwip/opt.h"

#include "lwip/memp.h"

#include "lwip/pbuf.h"
#include "lwip/udp.h"
#include "lwip/raw.h"
#include "lwip/tcp.h"
#include "lwip/api.h"
#include "lwip/api_msg.h"
#include "lwip/tcpip.h"

#include "lwip/sys.h"
#include "lwip/stats.h"

struct memp
{
        struct memp *next;
};


static struct memp *memp_tab[MEMP_MAX];

static const u16_t memp_sizes[MEMP_MAX] =
        {
                sizeof(struct pbuf),
                sizeof(struct raw_pcb),
                sizeof(struct udp_pcb),
                sizeof(struct tcp_pcb),
                sizeof(struct tcp_pcb_listen),
                sizeof(struct tcp_seg),
                sizeof(struct netbuf),
                sizeof(struct netconn),
                sizeof(struct api_msg),
                sizeof(struct tcpip_msg),
                sizeof(struct sys_timeout)
        };

static const u16_t memp_num[MEMP_MAX] =
        {
                MEMP_NUM_PBUF,
                MEMP_NUM_RAW_PCB,
                MEMP_NUM_UDP_PCB,
                MEMP_NUM_TCP_PCB,
                MEMP_NUM_TCP_PCB_LISTEN,
                MEMP_NUM_TCP_SEG,
                MEMP_NUM_NETBUF,
                MEMP_NUM_NETCONN,
                MEMP_NUM_API_MSG,
                MEMP_NUM_TCPIP_MSG,
                MEMP_NUM_SYS_TIMEOUT
        };




#if !SYS_LIGHTWEIGHT_PROT
static sys_sem_t mutex;
#endif

#if MEMP_SANITY_CHECK
static int
memp_sanity(void)
{
        s16_t i, c;
        struct memp *m, *n;

        for (i = 0; i < MEMP_MAX; i++) {
                for (m = memp_tab[i]; m != NULL; m = m->next) {
                        c = 1;
                        for (n = memp_tab[i]; n != NULL; n = n->next) {
                                if (n == m) {
                                        --c;
                                }
                                if (c < 0) return 0; /* LW was: abort(); */
                        }
                }
        }
        return 1;
}
#endif /* MEMP_SANITY_CHECK*/


// We use malloc to allocate memp because malloc() returns 8-byte alignment pointer, and pointer is four bytes long, so
// we always get a 4-byte alignment memory space
void memp_init(void)
{
        struct memp *m;
        u16_t i, j;
        u16_t size;

#if MEMP_STATS
        for (i = 0; i < MEMP_MAX; ++i) {
                lwip_stats.memp[i].used = lwip_stats.memp[i].max =
                                                  lwip_stats.memp[i].err = 0;
                lwip_stats.memp[i].avail = memp_num[i];
        }
#endif /* MEMP_STATS */


        for (i = 0; i < MEMP_MAX; ++i) {
                size = MEM_ALIGN_SIZE(memp_sizes[i] + sizeof(struct memp));
                if (memp_num[i] > 0) {
                        m = (struct memp *)malloc(size);
                        LWIP_ASSERT("NOT enough memory for memp_init!!!!!!!!!!!!!!!!!\n", (m != NULL));
                        memp_tab[i] = m;

                        for (j = 0; j < memp_num[i] - 1; ++j) {
                                m->next = (struct memp *)malloc(size);
                                LWIP_ASSERT("NOT enough memory for memp_init!!!!!!!!!!!!!!!!!\n", (m->next != NULL));
                                m = m->next;
                        }
                        m->next = NULL;
                } else {
                        memp_tab[i] = NULL;
                }
        }

#if !SYS_LIGHTWEIGHT_PROT
        mutex = sys_sem_new(1);
#endif


}

void *memp_malloc(memp_t type)
{
        struct memp *memp;

#if SYS_LIGHTWEIGHT_PROT
        SYS_ARCH_DECL_PROTECT(old_level);
#endif

        LWIP_ASSERT("memp_malloc: type < MEMP_MAX", type < MEMP_MAX);

#if SYS_LIGHTWEIGHT_PROT
        SYS_ARCH_PROTECT(old_level);
#else /* SYS_LIGHTWEIGHT_PROT */
        sys_sem_wait(&mutex);
#endif /* SYS_LIGHTWEIGHT_PROT */

        memp = memp_tab[type];

        if (memp != NULL) {
                memp_tab[type] = memp->next;
                memp->next = NULL;
#if MEMP_STATS
                ++lwip_stats.memp[type].used;
                if (lwip_stats.memp[type].used > lwip_stats.memp[type].max) {
                        lwip_stats.memp[type].max = lwip_stats.memp[type].used;
                }
#endif /* MEMP_STATS */

#if SYS_LIGHTWEIGHT_PROT
                SYS_ARCH_UNPROTECT(old_level);
#else /* SYS_LIGHTWEIGHT_PROT */
                sys_sem_signal(&mutex);
#endif /* SYS_LIGHTWEIGHT_PROT */

                LWIP_ASSERT("memp_malloc: memp properly aligned",
                            ((mem_ptr_t)((u8_t *)memp + sizeof(struct memp)) % MEM_ALIGNMENT) == 0);

                return (void *)((u8_t *)memp + sizeof(struct memp));

        } else {
                LWIP_DEBUGF(MEMP_DEBUG | 2, ("memp_malloc: out of memory in pool %"S16_F"\n", type));

#if MEMP_STATS
                ++lwip_stats.memp[type].err;
#endif /* MEMP_STATS */

#if SYS_LIGHTWEIGHT_PROT
                SYS_ARCH_UNPROTECT(old_level);
#else /* SYS_LIGHTWEIGHT_PROT */
                sys_sem_signal(&mutex);
#endif /* SYS_LIGHTWEIGHT_PROT */

                return NULL;
        }
}

void
memp_free(memp_t type, void *mem)
{
        struct memp *memp;

#if SYS_LIGHTWEIGHT_PROT
        SYS_ARCH_DECL_PROTECT(old_level);
#endif /* SYS_LIGHTWEIGHT_PROT */

        if (mem == NULL) {
                return;
        }

        memp = (struct memp *)((u8_t *)mem - sizeof(struct memp));

#if SYS_LIGHTWEIGHT_PROT
        SYS_ARCH_PROTECT(old_level);
#else /* SYS_LIGHTWEIGHT_PROT */
        sys_sem_wait(&mutex);
#endif /* SYS_LIGHTWEIGHT_PROT */

#if MEMP_STATS
        lwip_stats.memp[type].used--;
#endif /* MEMP_STATS */

        memp->next = memp_tab[type];
        memp_tab[type] = memp;

#if MEMP_SANITY_CHECK
        LWIP_ASSERT("memp sanity", memp_sanity());
#endif

#if SYS_LIGHTWEIGHT_PROT
        SYS_ARCH_UNPROTECT(old_level);
#else /* SYS_LIGHTWEIGHT_PROT */
        sys_sem_signal(&mutex);
#endif /* SYS_LIGHTWEIGHT_PROT */
}

